How To Fix CNV_DMC_MC020 - Field name '&' cannot only consist of a namespace prefix

SAP Error Message - Details

• Message type: E = Error

• Message class: CNV_DMC_MC - Migration Object Modeler

• Message number: 020

• Message text: Field name '&' cannot only consist of a namespace prefix

Self-Explanatory Message

Since SAP believes that this specific error message is 'self-explanatory,' no more information has been given.The majority of messages in the SAP system have a message text, however this is frequently insufficient to comprehend or resolve the problem.

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Smart SAP Assistant

• What is the cause and solution for SAP error message CNV_DMC_MC020 - Field name '&' cannot only consist of a namespace prefix ?

  The SAP error message CNV_DMC_MC020 indicates that there is an issue with a field name in the context of a Data Migration Cockpit (DMC) or a similar data migration process. The specific error message states that the field name cannot consist solely of a namespace prefix, which typically means that the field name is not valid because it does not include a proper identifier after the namespace.
  Cause:
  
  Invalid Field Name: The field name provided is likely formatted incorrectly. In SAP, field names often follow a specific naming convention that includes a namespace (like Z or Y for custom fields) followed by an identifier. If the field name is just a namespace (e.g., Z_ or Y_), it will trigger this error.
  Configuration Issues: There may be issues in the configuration of the data migration project where field mappings or definitions are not set up correctly.
  Data Model Issues: The data model being used for the migration may have fields defined incorrectly or missing proper identifiers.
  
  Solution:
  
  
  Check Field Names: Review the field names being used in your data migration project. Ensure that all field names follow the correct naming conventions and include valid identifiers after the namespace prefix.
  
  For example, instead of using Z_, use Z_FIELDNAME.
  
  
  
  Update Configuration: If the error arises from a configuration file or mapping, update the relevant configuration to ensure that all field names are valid.
  
  
  Review Data Model: If you are using a custom data model, check the definitions of the fields to ensure they are correctly defined with proper names.
  
  
  Testing: After making the necessary changes, test the migration process again to ensure that the error has been resolved.
  
  
  Related Information:
  
  SAP Notes: Check SAP Notes related to the Data Migration Cockpit or the specific error message for any additional guidance or patches that may address this issue.
  Documentation: Refer to the official SAP documentation for guidelines on naming conventions and data migration best practices.
  Community Forums: Engage with SAP community forums or support channels where similar issues may have been discussed, and solutions shared.
  
  By following these steps, you should be able to resolve the CNV_DMC_MC020 error and proceed with your data migration successfully.